UBR Frequency difference listed on spec sheet

the UBR spec sheet lists Different freq’s for Cellular 1 and 2 (UBR-LTE-US-T-PRM)
Cellular 1: B2, B4, B5, B12, B13, B25, B26
Cellular 2: B2, B4, B5, B12, B13, B14, B66, B71

I understand that one chip is sierra and the other is qualcomm… but will this stay the same? What benefit does it offer.